1. Field of the Invention
The present invention relates to an electromagnetic fuel injection valve which is used in an internal combustion engine and which drives a valve body due to an electromagnetic force to inject fuel.
2. Description of the Prior Art
In an electromagnetic operating type injection valve described in Japanese Patent Unexamined Publication No. 10-122085, a valve body is constituted by a valve closing body 10 connected to the end portion of a connection tube 11 by welding and a movable element 12, and is guided by a guide flange 15 provided in an intermediate member 6. On the contrary, a magnetic passage is constituted by a fuel inflow tube piece 1, serving as a core surrounded by an electromagnetic coil 4, at least one guide element 16, serving as a ferromagnetic element formed as a yoke, a connection member 14, brought into contact with another end portion of the guide element 16, and the movable element 12. At this time, a gap portion (a void portion in a direction crossing a valve axis (in a diametrical direction) is formed between an outer peripheral surface of the movable element 12 and an inner peripheral surface of the connection member 14, and a side magnetic passage (referred to as a side gap in the present invention) is formed in the gap portion.
In the electromagnetic fuel injection valve in accordance with the conventional structure, in order to restrict a dispersion in the side gap, it is necessary to secure a coaxiality between the intermediate member 6 and the connection member 14, and also a coaxiality between a seat surface of a seat body 8 and the connection member 14. It is also necessary when assembling the parts to secure both of them with a high accuracy. Accordingly, a working process becomes difficult and the cost therefore becomes expensive. These problems become significant as the injection valve becomes narrower, and, as a result, it becomes difficult to keep the required working accuracy. It also becomes difficult to maintain the required injection accuracy due to an eccentricity and an incline of the valve body which occur in the conventional structure.
The present invention was made to solve the disadvantages mentioned above, and an object of the present invention is to provide a valve structure that works easily, does not increase production cost, can reduce a dispersion in a side gap by restricting an eccentricity and an incline of a valve body, and can maintain a high injection accuracy high.
An electromagnetic fuel injection valve in accordance with the present invention has a gap portion (i.e., a side gap portion) in a direction crossing a valve axis (in a diametrical direction) in a magnetic passage for driving a valve body. In accordance with the present invention, the structure is made such that the gap portion and a guide portion for guiding a movement in a direction of the valve axis of the valve body are constructed within the same member (one member). That is, the member corresponds to a member provided in an outer peripheral portion of the valve body along the valve axis, and the member may be a nozzle body in which a fuel injection hole and a valve seat are formed or the member may be an independent member for supporting the nozzle body, for example, a nozzle guide body.